By melding traditional Latin rhythms to their already scathing metal melee, Brazilian bred Sepultura crafted their own unique sub-genre of metal, one which judiciously mixed world music groove with turgid metal thunder. The result was a one-of-a-kind maelstrom that only former member Max Cavalera has been able to replicate via his offshoot outfit Soulfly. Formed in Belo Horizonte, Brazil, Sepultura churned out five impressive albums before landing upon this, their signature sound. The blend of crazy rhythms and crunching guitars that saturated Roots without a doubt brought invigorated creativity to the '90s metal scene. SD

22. Ozzy - Diary of a Madman (Jet Records, 1981)

Ozzy's sophomore album is easily on par with Blizzard of Ozz. Tracks like "Over The Mountain," "Flying High Again," and the title track show why Randy Rhoads was one of the genre's greats. The album has something of a bittersweet legacy, as well, since Rhoads died in a plane crash shortly after the album's release while the band was on tour. SD

21. Iron Maiden - Piece of Mind (Capitol Records, 1983)

One of the true innovators of heavy metal, Iron Maiden is a true giant of the genre. Piece of Mind is a landmark release that showed the best of the band's classic line-up and gave the world some of the best technical metal ever recorded. ET

20. Deep Purple - Machine Head (Warner Bros., 1972)

One of the true testaments of a band is if one of their album titles or song titles is eventually scooped up by some youngsters and used as a band name. In the case of Deep Purple, Machine Head was given such honors by Robert Flynn. But more importantly than the homage that Flynn and his bandmates have bestowed upon DP, is the fact that the band's sixth studio effort (they had two live albums tossed into the mix prior to this release, as well) is the album that basically put them on the map for all heavy metal eternity. How so? Due to the oft mimicked, never repeated glory of the riff that is "Smoke On The Water." That song alone was enough to place Deep Purple in the metal hall of fame, alongside Sabbath. SD